Method of forming knock-out plugs



Nov. 17, 1936. I H, E, HASSE 2,060,863

METHOD OF FORMING KNOCK-OUT PLUGS Filed June 23, 1934 l b v fi'ez'rzrz'clz fi/Yaase I I INVENTOR t ATTORNEY Patented Nov. 17, 1936 UNITED STATES PATENT OFFICE IVIETHOD OF FORMING KNOCK-OUT PLUGS Heinrich E. Haase, Chicago, 111., assignor to Industrial Patents Corporation, Chicago, 111., a corporation of Delaware Application June 23, 1934, Serial No. 732,039

9 Claims.

1 titled Container and method of making same.

Other objects of the invention will be apparent from the description and claims which follow.

This application is a continuation in part of the application filed by me on September 17, 1932, Serial Number 633,660.

Referring now to the drawing in which identical reference characters in the several figures refer to identical parts:

Figure 1 is a perspective view of a container, partly broken away, illustrating a series of sifter openings sealed with knock-out plugs formed by the method of the present invention. In this figure one of the plugs is shown being removed from its respective opening.

Figure 2 is a plan view of the top of the container shown in Figure 1.

Figure 3 is a sectional view through one of the sifter holes and plugs.

Figure 4 is a fragmentary sectional view showing, a portion of a strip of fiber board, a single punch element, a plug partially removed from the strip, and a plug restorer.

It will be seen that the cylindrical container having side walls I may be provided with any desired type of bottom 2 and a top 3. The top is shown as secured to the side walls I by metal ferrule 4 which is of the type more particularly described in the aforesaid Patent No. 1,959,971 to Charles T. Walter. The perforations 5 are closed by knock-out plugs 6 which are made of the same material as the cover 3. The plugs result from the formation of the perforations or openings 5.

In the embodiment of the invention, illustrated in the drawing, the cover 3 is made of fiber board of appropriate thickness. In this embodiment of the invention the holes are first cut by any means such as a punch press and the material, or plugs 9, sheared out of the holes 5 is pressed back into the opening in which it wedges tightly and securely. Where desired, the operation of cutting the openings and forcing the mateiral cut from and in displaced position back into the holes can be readily accomplished on the punch press. In other words, while the fibers between the plugs 6 and the wall are completely sheared, the plug is not entirely removed from the hole 5 during this operation.

When the plugs are sheared from a sheet of fibrous material having a thickness, for example, of approximately or more with a suitable punch or die or other suitable means, the fibers between the plug and the Walls of the openings or holes are completely severed and the plugs in this severing operation are forced partly out,

The plugs preferably half way, of the openings or holes 5.

6 are not forced entirely out of the openings or holes 5 but they are displaced or offset slightly by being forced partly out of the openingsor holes during the severing operation. The plugs are, retained partly within the respective holes-0r openings 5 so that the plugs thus formed can be readily pushed back into their original flush position with relation to the sheet of fibrous material, that is, the plugs may be pushed back from their displaced or offset position to a wedging position in their respective openings or holes and preferably with the inner and outer faces of the plugs lying in the planes of the inner and outer faces of the body material and wedged therein without having to expand the plugs or contract the holes or openings around the plugs. The natural tendency of the sheared plugs, after the shearing action, to expand to tightly fit the openings or holes is sufficient to insure an effective wedging action of the plugs in the openings or holes and the openings or holes provide for guidance of the plugs in the movements of the plugs from the said displaced or offset positions to their flush positions with relation to the body material. The result is that no mechanical difficulty is experienced in forcing or pushing the partly unseated plugs back into the openings or holes and yet these plugs may be readily pushed entirely out of the respective openings when desired for sifting purposes.

, Inpractice, the knock-out plugs are completely severed from the sheet material and moved partly out of the resulting openings or holes through the instrumentality of a punch or die press or other means and without taking the material from such punch or die press or other means, the plugs are reseated in their respective openings with the faces of the plugs flush with the faces of the body material, as for instance, r

openings.

A simple means'for performing this step is shown in Figure 4. In this figure the fiber board 3 is shown resting on punch press platform it. Punch element 9 is shown at the lower limit of its stroke with plug 6 completely severed but not entirely dislodged from fiber board 3.- Spring it is seated in socket ll between washers l2 and i3. Upon the up stroke of punch 9 spring it? urges washer l3 upwardly, thus forcing plug 6 back into hole where it is tightly and securely wedged. Any resilient means may be substituted for spring l8, as, for example, rubber, it being merely necessary that the resilient means be such as to cease the upward motion of washer l3 flush with the top of platform M.

It will be seen that the present invention brings about simplified construction and manufacturing, requires a minimum of machinery and brings about a saving due to the fact that the plugs result from the formation of the openings or holes 5 and are used to plug the openings or holes 5.

I am aware of the fact that sifter top containers have been devised from time to time in which the holes are formed by partial scoring but not entirely cutting out the plugs. Such container tops, however, are not successfully adapted to fiber top containers inasmuch as considerable difiiculty is encountered in removing the plugs unless they are completely sheared and severed at all portions of the periphery.

Where metal tops, as disclosed for example in the patent to Harbeck, No. 853,547, are used, the plugs may be bent down and removed as an obstruction in this manner. In the case of the fiber top, however, due to the nature of the material, the plugs may not be so bent down satisfactorily and are difficult to remove without tearing and mutilating the top of the container.

The present invention provides a novel method for forming knock-out plugs in a container top or sifting portion which is inexpensive and entirely satisfactory for packages containing powder and dry or granulated substances, such as cleansers and the like.

It will be noted by reference to Figure 1 that the plugs 6 are very easily removed by tapping with an instrument I which may be a nail or the tine of a fork or other household instrument. The instrument is shown in Figure 1 as being held in a human hand 8.

While the plugs are completely sheared and severed at all portions of the peripheries thereof they are not separated from the fibrous body or sheet material and scattered but instead are returned within their respective openings in the fibrous body or sheet material, and if desired with their inner and outer faces arranged in the planes of the inner and outer faces of the body or sheet material.

I claim:

1. The method of forming readily openable sealed openings in a fiat fibrous body which comprises shearing plugs from the fibrous body in such a manner as to completely sever all of the fibers without removing the plugs from the openings and thereafter securing said plugs in said openings in tight wedging relation with the openings and with the opposite faces of the plugs lying in the planes of the inner and outer faces of the fibrous body.

2. The method of forming readily openable' sealed openings in a fiat fibrous body which comprises forming openings by the displacement of plugs in the formation of said openings, supporting said plugs in displaced position in the openings and replacing said plugs in the openings with the opposite faces of the plugs in the planes of the inner and outer fiat faces of the fibrous body.

3. The method of forming readily openable sealed openings in a fiat fibrous body which comprises entirely severing plugs and thereby forming openings in said fibrous body without entirely removing said plugs from said openings and thereafter returning said plugs into wedging relationship with the openings and with the opposite faces of the plugs lying in the planes of the inner and outer faces of the fibrous body.

4. The method of forming readily openable sealed openings in a fiat fibrous body which comprises shearing plugs from said fibrous body in such a manner as to completely sever all fibers without completely removing the plugs from the openings whereby the openings serve as a guide for the return of the plugs in tight wedging relationship with the openings, with the opposite faces of the plugs lying in the planes of the inner and outer faces of the fibrous body.

5. The method of forming readily openable sealed openings in a fiat fibrous body which comprises shearing plugs from said fibrous body in such a manner as to completely sever all fibers Without completely removing the plugs from the openings whereby the openings serve as a guide for the return of the plugs in tight wedging relationship with the openings, with the opposite faces of the plugs lying in the planes of the inner and outer faces of the fibrous body and removable from the openings by a light mechanical pressure.

6. The method of forming knock-out plugs which comprises forming perforations in fibrous material by shearing plugs therefrom in such a manner as to completely sever all of the fibers without removing the plugs from the perforations and thereafter securing said plugs in said perforations in tight wedging relationship.

7. The method of forming knock-out plugs which comprises forming perforations in a sheet of fibrous material by the displacement of plugs in the formation of the perforations, supporting the plugs in displaced position in the perforations and thereafter replacing the plugs in the perforations in tight wedging relationship.

8. The method of forming knock-out plugs which comprises forming perforations in a sheet of fibrous material by completely severing plugs therefrom without entirely removing the plugs from the perforations and thereafter returning the plugs into wedging relationship with the perforations.

9. The method of forming knock-out plugs which comprises forming perforations in a sheet of fibrous material by shearing plugs therefrom in such a manner as to completely sever all of the fibers without completely removing the plugs from the perforations whereby the perforations serve as guides for the return of the plugs in tight wedging relationship with the perforations.

HEINRICH E. HAASE. 

